Added GLU activation function and Gated activation function

[hazemessamm]

Proposed changes

1. Added GLU activation function.
2. Added Gated activation function.

Checklist

Put an x in the boxes that apply.

• [x] I have read the CONTRIBUTING document
• [x] I have run pre-commit run --all-files to format my code / installed pre-commit prior to committing changes
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] I have updated the necessary documentation (if needed)